This present embodiments relate to medical diagnostic ultrasound. In particular, suppression of motion artifacts is provided for medical diagnostic ultrasound.
When imaging flow, the sonographer may move a transducer relative to a patient in an effort to identify a region of interest. When color, flow imaging is active, the motion may be detected as flow, causing a flash or motion artifact.
Motion artifacts may be suppressed. The shift in the clutter spectrum due to motion is determined. The clutter spectrum is frequency mixed with an equal but opposite shift. The mixing brings the clutter peak to DC. A wall filter removes information at DC. The wall filter cutoff may also change as a function of the amount of shift.
Motion does not necessarily cause a shift in clutter spectrum. Only the axial component of the motion produces a shift in the clutter spectrum. The lateral component produces little or no shift. Shifting the distorted spectrum to DC may not be effective in situations with lateral motion.
Axial motion also distorts the symmetry of the clutter spectrum. The degree of distortion depends on the amount of motion. Without motion, the clutter spectrum is normally mostly symmetric. Shifting the distorted spectrum to DC is not only non-effective, but sometimes detrimental because of the false detection after wall filtering.